//
//  WBNavigationController.swift
//  微博
//
//  Created by dong on 2017/11/15.
//  Copyright © 2017年 dong. All rights reserved.
//

import UIKit

class WBNavigationController: UINavigationController {
    
    override func viewDidLoad() {
        super.viewDidLoad()
        
        //隐藏默认的NavigationBar
        navigationBar.isHidden = true
    }
    
    ///重写push方法,所有push动作都会调用此方法
    ///viewcontroller是被push的控制器，设置他的左侧按钮作为返回按钮
    override func pushViewController(_ viewController: UIViewController, animated: Bool) {
        
        //如果不是栈底控制器才需要隐藏，根控制器不需要处理
        if childViewControllers.count > 0 {
            //隐藏底部的TabBar
            viewController.hidesBottomBarWhenPushed = true
        
        
        //判断控制器的类型
        if let vc = viewController as? WBBaseViewController{
            
            var title = "返回"
            
            
            //判断控制器级数
            if childViewControllers.count == 1{
                //title显示首页标题
                title = childViewControllers.first?.title ?? "返回"
            }
            
            //取出自定义的navItem,设置左侧按钮作为返回按钮
            vc.navItem.leftBarButtonItem = UIBarButtonItem(title: title, target: self, action: #selector(popToParent),isBack:true)
            }
        }
        
        super.pushViewController(viewController, animated: true)
    }
    func popToParent(){
        popViewController(animated: true)
    }
}
